ACTG 372: The purpose of this study is to: 1) see how long the study drugs will keep the amount of HIV in the blood at an undetectable level (less than 200 RNA copies/ml); 2) see if these drugs are safe to take in combination and how well they are tolerated. The following drugs will be used: zidovudine (ZDV) or stavudine (d4T); lamivudine (3TC); indinavir (IDV); and abacavir (ABC, 1592U89). ZDV, d4T, and 3TC are nucleoside analogs which are FDA-approved drugs for the treatment of HIV infection. Indinavir is an FDA-approved protease inhibitor, a type of anti-HIV drug that prevents the virus from maturing and infecting other cells. Studies have shown that protease inhibitors are more effective when used with other anti-HIV drugs than when used alone. Abacavir (ABC) is a newly approved anti-HIV drug which has been tested in a limited number of volunteers in clinical trials. Early studies have shown that it may be helpful in preventing HIV from multiplying in the body.